Vergence Responses to a Base Out Prism
Elaine Cornell · 2024
During the course of an examination of suspected strabismus a base out prism may be used to induce a convergence response and confirm that binocular single vision is present. The diagnosis in these cases is made by observation of the saccadic and vergence responses to the prism. Perhaps the pattern most commonly described as normal is that the prism causes both eyes to make an equal conjugate movement of the full amount induced by the prism, followed by a vergence movement of the eye without the prism. 1